Re: operator precedence issues

On 2013-09-03 08:59:53 -0500, Merlin Moncure wrote:
> While playing around with Andres's trick, I noticed that it works but
> will not match against operators taking "any" although those will
> match with explicit schema declaration (FWICT it goes through the
> search_path trying to explicitly match int/int operator then goes
> again matches "any").  That's pretty weird:

Not surprising. We look for the best match for an operator and
explicitly matching types will be that. If there were no operator(int,
int) your anyelement variant should get called.

> Ideally though you could specify operator precedence in the operator
> name itself though in such a way that bison pick it up.  I don't know
> if that's possible since so many operator names have been given out
> without any thought to reserving characters for precedence, or if it
> would be worth the extra parsing time even if you could do it.
> Overriding stock operator behaviors is a really dodgy practice with
> the limited but important exception of handling certain classes of
> mathematical errors.

I have to say, even those it seems like it's primary advantage is
making it harder to read the code, but YMMV.

Greetings,

Andres Freund

-- Andres Freund                       http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training &
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